An interactive applet and associated web page that demonstrate equilateral triangles (all sides the same length).
The applet presents an equilateral triangle where the user can drag any vertex....More: lessons, discussions, ratings, reviews,...

Euclid's proposition shows that the exterior angle of an extended side of a triangle is greater than any of the interior angles of the triangle. The guide then examines the structure of the propositi...More: lessons, discussions, ratings, reviews,...

Drag the vertices of a quadrilateral or pentagon, and examine what happens to the angle measures and sum of the interior angles. Java Sketchpad activities, with guiding questions for students.More: lessons, discussions, ratings, reviews,...

An interactive applet and associated web page that demonstrate the relationship of the interior and exterior angles of a polygon.
The applet shows an irregular polygon where one vertex is draggabl...More: lessons, discussions, ratings, reviews,...

An interactive applet and associated web page that demonstrate the
interior angles that are formed where a transversal crosses two lines. The applets shows the
two possible pairs of angles in...More: lessons, discussions, ratings, reviews,...

The user learns about angles formed when a transversal cuts two lines, either parallel or intersecting. After viewing examples of the angles formed, users can interactively practice naming the angles...More: lessons, discussions, ratings, reviews,...

The user learns about polygons and how to find the sum of the interior angles of any given polygon. After viewing examples, users can interactively test their understanding of properties of polygons.More: lessons, discussions, ratings, reviews,...

GeoCon HD is designed to be used by students, teachers and math enthusiasts studying plane geometry. With GeoCon HD various constructions can be created with the touch of a finger. Resolve constructio...More: lessons, discussions, ratings, reviews,...

GeoCon is designed to be used by students, teachers and math enthusiasts studying plane geometry. With GeoCon various constructions can be created with the touch of a finger. Resolve construction task...More: lessons, discussions, ratings, reviews,...

This material is based upon work supported by the
National Science Foundation under Grant DUE-0226284.
Any opinions, findings, and conclusions or recommendations
expressed in this material are those of the author(s)
and do not necessarily reflect the views of the
National Science Foundation.